Cutaneous manifestations of cystic fibrosis.

Cystic fibrosis (CF) is caused by a mutation in the Cystic fibrosis transmembrane conductance regulator (CFTR) gene, and features recurrent sinus and pulmonary infections, steatorrhea, and malnutrition. CF is associated with diverse cutaneous manifestations, including transient reactive papulotranslucent acrokeratoderma of the palms, nutrient deficiency dermatoses, and vasculitis. Rarely these are presenting symptoms of CF, prior to pulmonary or gastrointestinal sequelae. Cutaneous drug eruptions are also highly common in patients with CF (PwCF) given frequent antibiotic exposure. Finally, CFTR modulating therapy, which has revolutionized CF management, is associated with cutaneous side effects ranging from acute urticaria to toxic epidermal necrolysis. Recognition of dermatologic clinical manifestations of CF is important to appropriately care for PwCF. Dermatologists may play a significant role in the diagnosis and management of CF and associated skin complications.

Fixed drug eruptions: presentation, diagnosis, and management.

Fixed drug eruption (FDE) is a well-defined, circular, hyperpigmenting plaque that recurs as one or a few lesions always in fixed locations upon ingestion of a drug. FDE commonly occurs on the genitals, lips, trunk, and hands. Although the lesions are distinctive, the diagnosis of FDE often is missed because it shares none of the characteristics of more common morbilliform drug rashes. The diagnosis can be confirmed by histopathologic examination of a small punch biopsy specimen. Drug avoidance is the mainstay of treatment, and antihistamines can reduce associated pruritus. Raising awareness of this condition will increase the likelihood of prompt diagnosis leading to resolution within days to weeks after the offending drug is discontinued.